open

Opens and returns an index instance located in
Configuration.getIndexDirectory(). The instantiation of the
native equivalent will fail, if the the given class of the index' value
type does not match the type of the index on disk.

close

Closes the searcher. Call this method in some cleanup code to cleanly
shutdown and to delete the native searcher. The searcher is then not
usable anymore.

contains

public boolean contains(java.lang.String key)

Convenience method to check, if the index contains some mapping for the
given key. Do not use this method, if you are going to lookup the
Postlist, if such a mapping exists. For that reasons try to
directly search the postlist and skip if empty.

getHead

Convenience method to search the Postlist.Head of some Postlist
if only interested in that meta-data. Do not use this method, if you are
going to lookup the entire postlist afterwards. For that reasons try to
directly search the postlist and skip if empty.

search

Returns a iterable Postlist for the given key. The postlist will
be truncated at the end to contain at most the first num elements.
The corresponding range is [0, num). Use this method to
efficiently lookup the wanted top-k entries.

search

Returns a iterable Postlist for the given key. The postlist will
be loaded from the index specified by begin with at most the
num following elements from that position. The corresponding
range is [begin, begin + num). If begin is not a valid
index the returned postlist will be empty.